Ralf Schumacher roared to pole position at the Canadian Grand Prix in Montreal as championship leader Kimi Raikkonen made a mistake which could cost him the lead in the championship.

The German took his second top spot in succession spearheading a one-two with Juan Pablo Montoya as the Williams-BMWs revelled on the Circuit Gilles Villeneuve which had finally dried out after a day of rain.

Schumacher took pole by almost 0.4seconds from Montoya - victorious in the last race in Monaco - with Ferrari's Michael Schumacher third.

But the five-time world champion's hopes of taking the lead in the title chase for the first time this season were boosted when Raikkonen made a total hash of his qualifying and ended up last.

Ferrari ace Schumacher trails Raikkonen by just four points, heading into today's race - the eighth round of the 16-race season - looking for a sixth victory here.

Schumacher finished more than half-a-second slower than his brother, with Fernando Alonso fourth - while Rubens Barrichello was fifth as the Ferraris were unable to maintain the superiority they enjoyed in the wet.

David Coulthard's hopes of forcing his way back into title contention with victory suffered a setback after another disappointing qualifying display as he starts 11th.

The 32-year-old Scot, who trails team-mate Raikkonen by 23 points, had admitted he needed to improve his displays over the single lap but paid for an error at the last chicane.

But his disappointment was nothing compared to Raikkonen's after he went too wide at a chicane and slid across the grass to ram backwards into a tyre barrier.

The Finn briefly kept the car going, but it then cut out, and he will start from last place on the grid for the second time in four races.

The last time he was in the same position - in Spain - he smashed into the back of Antonio Pizzonia's Jaguar on the grid and failed to finish on the podium for the only time this season.

Jenson Button, perhaps feeling some effects from his crash in Monaco two weeks ago, produced his worst qualifying performance of the season, finishing back in 17th place in his BAR-Honda.

Justin Wilson finished one place further back in 18th, while fellow Minardi driver Jos Verstappen will line up on the grid one row nearer.

The duo's boss Paul Stoddart, embroiled in a row over finances with his rival team chiefs, could finally concentrate on what was happening on the track as he warmly congratulated both his drivers after their qualifying efforts.

Jordan's Ralph Firman was unable to repeat his heroics in the wet in first qualifying when he was fourth-fastest as he finished 19th.

Firman nearly lost it at the first corner, and will have championship leader - for now - Raikkonen for company.